Framed E2 structures in Floer theory

Mohammed Abouzaid*, Yoel Groman, Umut Varolgunes

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


We resolve the long-standing problem of constructing the action of the operad of framed (stable) genus-0 curves on Hamiltonian Floer theory; this operad is equivalent to the framed E2 operad. We formulate the construction in the following general context: we associate to each compact subset of a closed symplectic manifold a new chain-level model for symplectic cohomology with support, which we show carries an action of a model for the chains on the moduli space of framed genus 0 curves. This construction turns out to be strictly functorial with respect to inclusions of subsets, and the action of the symplectomorphism group. In the general context, we appeal to virtual fundamental chain methods to construct the operations over fields of characteristic 0, and we give a separate account, over arbitrary rings, in the special settings where Floer's classical transversality approach can be applied. We perform all constructions over the Novikov ring, so that the algebraic structures we produce are compatible with the quantitative information that is contained in Floer theory. Over fields of characteristic 0, our construction can be combined with results in the theory of operads to produce explicit operations encoding the structure of a homotopy BV algebra. In an appendix, we explain how to extend the results of the paper from the class of closed symplectic manifolds to geometrically bounded ones.

Original languageEnglish
Article number109755
JournalAdvances in Mathematics
StatePublished - Jul 2024

Bibliographical note

Publisher Copyright:
© 2024


  • Floer theory
  • Operadic structures


Dive into the research topics of 'Framed E2 structures in Floer theory'. Together they form a unique fingerprint.

Cite this